In vivo filter assembly

ABSTRACT

Disclosed is an assembly for filtering debris flowing in an in vivo fluid stream, the assembly comprising at least one balloon configured to volumetrically expand and, during at least a portion of the expansion, operatively connect with a filter, and to contract following the expansion. The assembly further comprising a filter configured to operatively connect with the at least one balloon during at least a portion of the volumetric expansion of the at least one balloon, such that the filter expands during the operative connection in order to filter debris from a fluid flowing in a fluid stream within which the expanded filter is disposed.

FIELD OF THE INVENTION

The present invention relates generally to in vivo filters that filterdebris from a fluid stream in which the filter is disposed.

BACKGROUND OF THE INVENTION

In 1977 Andreas Gruntzig performed the first successful balloonangioplasty on an obstructed human artery, thereby opening the vesseland allowing improved flow of blood.

Balloon angioplasty is a catheter-based procedure in which a long, thintube with a deflated balloon at the tip is inserted into an artery. Theballoon is guided to a stenotic lesion using X-ray fluoroscopy, rapidlyinflated to a pressure of several atmospheres and deflated. Severalrounds of inflation and deflation cause the stenotic lesion to crack andsquash radially outward, thereby opening the obstructed lumen.

Balloon Angioplasty may be indicated for improving circulation tovirtually any stenosed organ vasculature or peripheral vasculature,including opening occluded vessels during an acute heart attack; and inplace of surgical endarterectomy, treatment of carotid artery stenosis,in high-risk surgical patients.

A problem associated with balloon angioplasty is that the stenoticlesion may release debris that travels to vital organs, for example thebrain and/or lungs, causing vascular blockage, tissue necrosis and/orpatient death.

To prevent such draconian sequela, a number of in vivo debris filterdevices have been developed that are designed to capture debris releasedfrom stenotic lesions during an angioplasty procedure.

Using a guide passage, such a debris filter is positioned downstream ofthe intended angioplasty site and expanded to press against the tissuesurrounding the lumen, thereby effectively filtering all blood passingthrough the lumen. A balloon angioplasty catheter is then introducedinto the artery and the balloon is positioned adjacent the stenoticlesion. The balloon is inflated, the lesion releases debris and thefilter captures the debris. After deflation and removal of the balloon,the filter is contracted and removed with the captured debris.

The use of in vivo debris filters during balloon angioplasty, however,may fail to prevent vascular blockage, tissue necrosis and/or patientdeath. To be effective, in vivo debris filters are positioned quite adistance downstream from the lesion undergoing angioplasty; considerablyraising the chances that a vessel branching off the treated vessel willbe located between the angioplasty balloon and the filter. Debrisgenerated by the angioplasty will likely find its way into the branchvessel and travel to the lungs or brain, causing the above-notedsequela.

Additionally the filter itself may pose a health hazard to the patient.The deployment zone for the filter often comprises healthy vasculartissue. Positional adjustments and expansion of the filter against thehealthy vascular tissue can cause tissue scars and plaques that, ofthemselves, provide a breeding ground for additional, full-blown,stenotic lesions.

In spite of the above-noted risk and health hazard, use of a debrisfilter is indicated for patients having “rupture-prone” lesions;stenotic lesions characterized by thin fibrous caps and large lipidcores. Even though it is impossible to introduce a filter once theballoon angioplasty has begun, in theory, pre-operative identificationof a rupture-prone stenotic lesion would allow the patient and surgeonto weigh the risks and benefits of using an in vivo debris filter inaddition to the angioplasty balloon catheter.

Unfortunately, the above theoretical solution is almost totallyunworkable in practice because the very lesions that are rupture-proneare often not visible by x-ray angiography.

(Z. A. Fayad et al: “Clinical Imaging of the High-Risk or VulnerableAtherosclerotic Plaque”; Circulation Research. 2001; 89: 305.)

The surgeon and patient, therefore, are left to grope in the dark foranswers as to whether to risk patient health and deploy a debris filter.

In general, existing devices and technology present a number ofadditional disadvantages associated with the stand-alone in vivo debrisfilter, including:

-   -   1) the additional thousands of dollars to pay for each        disposable filter for each surgery;    -   2) the difficulty in surgically deploying the filter in addition        to a balloon angioplasty; and    -   3) the additional surgical fee charged by the surgeon for        performing a second surgical procedure associated with the        filter.

SUMMARY OF THE INVENTION

Some embodiments of the present invention successfully address at leastsome of the shortcomings of the prior art by providing an assembly forfiltering debris flowing in an in vivo fluid stream, the assemblycomprises a balloon configured to volumetrically expand and, during atleast a portion of the expansion, operatively connect with a filter,thereby expanding the filter.

There is thus provided an assembly for filtering debris flowing in an invivo fluid stream, the assembly comprising at least one balloonconfigured to volumetrically expand and, during at least a portion ofthe expansion, operatively connect with a filter, and to contractfollowing the expansion. The assembly further comprising a filterconfigured to operatively connect with the at least one balloon duringat least a portion of the volumetric expansion of the at least oneballoon, such that the filter expands during the operative connection inorder to filter debris from a fluid flowing in a fluid stream withinwhich the expanded filter is disposed.

In embodiments, the at least one balloon comprises at least one proximalportion and at least one distal portion. In embodiments, and theoperative connection between the at least one balloon and the filteroccurs in the at least one proximal portion. In embodiments, theoperative connection between the at least one balloon and the filteroccurs in the at least one distal portion.

In embodiments, a maximal expansion diameter of the at least one distalportion is greater than a maximal expansion diameter of the at least oneproximal portion. In embodiments, a maximal expansion diameter of the atleast one proximal portion is greater than a maximal expansion diameterof the at least one distal portion.

In embodiments, the at least one balloon comprises at least oneangioplasty balloon. In embodiments, the at least one balloon comprisesat least two balloons, at least one first balloon and at least onesecond balloon.

In embodiments, the at least one first balloon is positioned proximallyto the at least one second balloon. In embodiments, the at least onefirst balloon has a first maximal inflation diameter and the at leastone second balloon has a second maximal inflation diameter.

In embodiments, at least a portion of the filter is configured toremovably connect to a luminal aspect associated with the fluid stream,in response to pressure by the at least one balloon of between at leastabout one atmosphere and no more than about 20 atmospheres.

In embodiments, at least a portion of the filter is configured to remainremovably connected to the luminal aspect during the contraction of theat least one balloon. In embodiments, the at least one balloon isconfigured to sequentially pass through at least two sequences of theexpansion and contraction of the at least one balloon.

In embodiments, at least a portion of the filter is configured to remainremovably connected to a luminal aspect associated with the fluid streamduring at least a portion of the at least two sequences.

In embodiments, the assembly includes at least one cord operativelyassociated with the filter and configured to disconnect at least aportion of the filter from the luminal aspect when tension is applied tothe at least one cord.

In embodiments, at least a portion of the filter is configured todisconnect from the luminal aspect in response to tension applied to theat least one cord of at least about one Newton.

In embodiments, at least a portion of the filter is configured todisconnect from the luminal aspect in response to tension applied to theat least one cord of no more than about 20 Newtons.

In embodiments, at least a portion of the filter includes apressure-sensitive adhesive having an affinity for a tissue associatedwith an in vivo luminal aspect.

In embodiments, the adhesive is an adhesive from the group of adhesivescomprising fibrin, biological glue, collagen, hydrogel, hydrocolloid,collagen alginate, and methylcellulose.

In embodiments, at least a portion of the filter is configured toremovably connect to a luminal aspect associated with the fluid stream,in response to pressure by the at least one balloon of between at leastabout one atmosphere and no more than about 20 atmospheres.

In embodiments, at least a portion of the filter is configured to remainremovably connected to the luminal aspect during the contraction of theat least one balloon.

In embodiments, the at least one balloon is configured to sequentiallypass through at least two sequences of the expansion and contraction ofthe at least one balloon.

In embodiments, at least a portion of the filter is configured to remainremovably connected to the luminal aspect during at least a portion theat least two sequences.

In embodiments, the assembly includes at least one cord operativelyassociated with the filter and configured to disconnect at least aportion of the filter from the luminal aspect when tension is applied tothe at least one cord.

In embodiments, at least a portion of the filter is configured todisconnect from the luminal aspect in response to tension applied to theat least one cord of at least about one Newton.

In embodiments, at least a portion of the filter is configured todisconnect from the luminal aspect in response to tension applied to theat least one cord of no more than about 20 Newtons.

In embodiments, the assembly includes a compression sleeve comprising asubstantially curved wall having a proximal end, a distal end and alumen extending from the proximal end to the distal end, the lumenhaving a cross sectional diameter that is substantially smaller than themaximal cross sectional diameter of the luminal aspect and at least onecord operatively associated with the filter, at least a portion of theat least one cord slidingly juxtaposed within the compression sleevelumen, such that in response to at least one first distal sliding of thesleeve while the at least one cord is held stationary, the filter iscaused to disconnect from the luminal aspect.

In embodiments, in response to at least one second distal sliding of thesleeve while the at least one cord is held stationary, the filter iscaused to radially contract such that a maximal cross sectional diameterof the filter is smaller that a cross sectional diameter of the sleevelumen.

In embodiments, in response to at least one third distal sliding of thesleeve while the at least one cord is held stationary; at least aportion of the filter is caused to enter the sleeve lumen.

In embodiments, the at least one balloon comprises an outer wall havinga distal end and a proximal end and an inner wall defining a lumen, thelumen extending from the distal end to the proximal end, and

In embodiments, at least a portion of the at least one cord isconfigured to slidingly pass through the lumen.

In embodiments, the at least one cord is configured to pull at least aportion of the filter into contact with the distal end of the at leastone balloon.

In embodiments, the assembly includes a catheter having a distal end anda proximal end and a lumen extending from the distal end to the proximalend, wherein the at least one balloon proximal end is operativelyassociated with the distal end of the catheter.

In embodiments, the at least one balloon lumen is substantiallycontinuous with the catheter lumen.

In embodiments, at least a portion of the at least one cord additionallyextends through the catheter lumen.

In embodiments, the filter includes a distal portion, a proximalportion, an opening to the filter associated with the proximal portionand at least one strut operatively associated with the proximal portion.

In embodiments, the assembly includes at least one cord operativelyassociated with the at least one strut, such that at least a portion ofthe opening is configured to contract radially inwardly in response totension applied to the at least one cord.

In embodiments, the at least one strut comprises at least two strutsoperatively associated with the at least one cord.

In embodiments, each of the at least two struts is configured toresiliently flex outward to form at least one expanded cross sectionaldiameter.

In embodiments, the at least one expanded cross sectional diameterdefines at least two sections, a first section having a first radius anda second section having a second radius.

In embodiments, the at least one strut comprises at least six strutsoperatively associated with the at least one cord.

In embodiments, the at least one cord comprises at least two cords andthe at least one strut comprises at least two struts.

In embodiments, the at least one cord comprises at least six cords andthe at least one strut comprises at least six struts.

In embodiments, the at least one balloon includes an inflation channelin fluid communication with an interior portion of the at least oneballoon, wherein the channel is configured to inflate the at least aportion of the at least one balloon by introduction of a fluid throughthe inflation channel.

In embodiments, the assembly includes a catheter comprising a curvedwall extending proximally from the at least one balloon and theinflation channel comprises a curved wall surrounding at least a portionof the catheter.

In embodiments, the at least one balloon comprises a material from thegroup consisting of: rubber, silicon rubber, latex rubber, polyethylene,polyethylene terephthalate, and polyvinyl chloride.

In embodiments, the filter includes a distal portion, a proximalportion, an opening to the filter associated with the proximal portion,and at least one cord guide channel circumferentially encircling atleast a portion the proximal portion. In embodiments, the assemblyincludes at least one cord, at least a portion of the at least one cordpasses through the guide channel, such that at least a portion of theopening is configured to contract radially inwardly in response totension applied to the at least one cord.

In embodiments, the filter comprises a flexible sheet material and theguide channel is formed from at least one of a bending of a portion ofthe sheet material, and a shaped component attached to the sheetmaterial.

In embodiments, the at least one cord channel comprises at least twocord channels located substantially on the same cross sectional plane ofthe filter and the at least one cord comprises at least two cords.

An assembly for filtering debris flowing in an in vivo fluid stream, theassembly comprising at least one balloon configured to volumetricallyexpand and, during at least a portion of the expansion, operativelyconnect with a filter, and to contract following the expansion, and afilter comprising a material having tissue connective properties for atissue associated with an in vivo fluid stream, the filter positioned tooperatively connect with the at least one balloon and removably connectto least a portion of the tissue and remain so connected during thecontractions of the at least one balloon.

In embodiments, the at least one balloon comprises at least one proximalportion and at least one distal portion. In embodiments, and theoperative connection between the at least one balloon and the filteroccurs in the at least one proximal portion.

In embodiments, the operative connection between the at least oneballoon and the filter occurs in the distal portion.

In embodiments, a maximal expansion diameter of the at least one distalportion is greater than a maximal expansion diameter of the at least oneproximal portion.

In embodiments, a maximal expansion diameter of the at least oneproximal portion is greater than a maximal expansion diameter of the atleast one distal portion.

In embodiments, the at least one balloon comprises at least oneangioplasty balloon. In embodiments, the at least one balloon comprisesat least two balloons, at least one first balloon and at least onesecond balloon.

In embodiments, the at least one first balloon is positioned distally tothe at least one second balloon. In embodiments, the at least one firstballoon has a first maximal inflation diameter that a maximal inflationdiameter of the second balloon.

In embodiments, at least a portion of the filter is configured toremovably connect to a luminal aspect associated with the fluid stream,in response to pressure by the at least one balloon of between at leastabout one atmosphere and no more than about 20 atmospheres.

In embodiments, the at least one balloon is configured to sequentiallypass through at least two sequences of the expansion and contraction ofthe at least one balloon. In embodiments, at least a portion of thefilter is configured to remain removably connected to a luminal aspectassociated with the fluid stream during at least a portion of the atleast two sequences.

In embodiments, the assembly includes at least one cord operativelyassociated with the filter and configured to disconnect at least aportion of the filter from a luminal aspect associated with the fluidstream when tension is applied to the at least one cord.

In embodiments, at least a portion of the filter is configured todisconnect from a luminal aspect associated with the fluid stream whenthe applied tension to the at least one cord is between at least aboutone Newton and no more than about 20 Newtons.

In embodiments, at least a portion of the filter includes apressure-sensitive adhesive having an affinity for a tissue associatedwith an in vivo luminal aspect. In embodiments, the adhesive is anadhesive from the group of adhesives comprising fibrin, biological glue,collagen, hydrogel, hydrocolloid, collagen alginate, andmethylcellulose.

In embodiments, at least a portion of the filter is configured toremovably connect to a luminal aspect associated with the fluid stream,in response to pressure by the at least one balloon of between at leastabout one atmosphere and no more than about 20 atmospheres.

In embodiments, the at least one balloon is configured to contractfollowing the expansion and at least a portion of the filter isconfigured to remain removably connected to the luminal aspect duringthe at least one balloon contraction.

In embodiments, the at least one balloon is configured to sequentiallypass through at least two sequences of the expansion and contraction ofthe at least one balloon.

In embodiments, at least a portion of the filter is configured to remainremovably connected to the luminal aspect during at least a portion theat least two sequences.

In embodiments, the assembly includes at least one cord operativelyassociated with the filter and configured to disconnect at least aportion of the filter from the luminal aspect when tension is applied tothe at least one cord. In embodiments, at least a portion of the filteris configured to disconnect from the luminal aspect in response totension applied to the at least one cord of between at least about oneNewton and no more than about 20 Newtons.

There is thus provided a method for collecting debris from a stenoticlesion associated with a primary stenotic vessel while preventingpassage of the debris into a branch vessel branching from the primaryvessel, the method comprising detecting the stenotic lesion in theprimary stenotic vessel, locating a filter in the primary stenoticvessel such that an opening of the filter is distal to a center of thestenotic lesion, locating at least a proximal portion an angioplastyballoon proximal to the opening in the filter, expanding the angioplastyballoon, contacting the opening of the filter with at least a distalportion of the angioplasty balloon during the expanding, causing thefilter to open during the contacting, generating debris from thestenotic lesion by the expanding of the angioplasty balloon, capturingthe debris in the filter, preventing passage of the debris into thebranch vessel by the contacting of the opening of the filter with the atleast a distal portion of the angioplasty balloon, contractingdisengaging the angioplasty balloon, and removing the angioplastyballoon from the primary stenotic vessel.

In embodiments, the method further comprises contracting the filter. Inembodiments, the method further comprises removing the filter from theprimary stenotic vessel.

There is thus provided a method for collecting debris within a bloodvessel, the method comprising juxtaposing an opening of an in vivodebris filter with at least one balloon, expanding the at least oneballoon in a blood vessel, opening the filter during the expansion ofthe at least one balloon, collecting debris within the filter,disengaging the at least one balloon from the filter, and removing theat least one balloon from the vessel.

In embodiments, the method further comprises contracting the filter, andremoving the filter from the blood vessel. In embodiments, the methodfurther comprises contacting a stenotic vascular lesion during theexpanding.

In embodiments, the method further comprises compressing the lesionduring the expanding. In embodiments the method further comprisesreleasing debris from the lesion during the compressing.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention for safely collecting debris using a debris filterpositioned in assembly with an angioplasty balloon is described by wayof example with reference to the accompanying drawings. With specificreference now to the drawings in detail, it is stressed that theparticulars shown are by way of example and for purposes of illustrativediscussion of the preferred method of the present invention only, andare presented in the cause of providing what is believed to be the mostuseful and readily understood description of the principles andconceptual aspects of the invention. In this regard, no attempt is madeto show structural details of the invention in more detail than isnecessary for a fundamental understanding of the invention, thedescription taken with the drawings making apparent to those skilled inthe art how the methods of the invention may be embodied in practice.

FIG. 1 a-1 d show deployment of an in vivo filter and balloon assemblyin a vessel shown in cross section, according to an embodiment of theinvention; and

FIGS. 2 a-2 d, 3 a-3 c, 4, and 5 a-5 e show alternative embodiments ofthe filter and balloon assembly shown in FIGS. 1 a-1 d, according to theinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to an in vivo filter that is biased to anopen position in conjunction with inflation of an angioplasty balloon.In an exemplary embodiment, during balloon inflation against a stenoticlesion, the balloon presses the outer surface of the filter into aluminal aspect directly upstream from the lesion to capture stenoticdebris. The filter maintains thus positioned throughout multipleangioplasty inflations and deflations, following which cords are used toremove the filter from the lumen.

The principles and uses of the teachings of the present invention may bebetter understood with reference to the accompanying description,Figures and examples. In the Figures, like reference numerals refer tolike parts throughout.

Before explaining at least one embodiment of the invention in detail, itis to be understood that the invention is not limited in its applicationto the details set forth herein. The invention can be implemented withother embodiments, and can be practiced or carried out in various ways.

It is also understood that the phraseology and terminology employedherein is for descriptive purpose and should not be regarded aslimiting.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which the invention belongs. In addition, the descriptions,materials, methods, and examples are illustrative only and not intendedto be limiting. Methods and materials similar or equivalent to thosedescribed herein can be used in the practice or testing of the presentinvention.

As used herein, the terms “comprising” and “including” or grammaticalvariants thereof are to be taken as specifying the stated features,integers, steps or components but do not preclude the addition of one ormore additional features, integers, steps, components or groups thereof.This term encompasses the terms “consisting of” and “consistingessentially of”.

As used herein, “a” or “an” mean “at least one” or “one or more”. Theuse of the phrase “one or more” herein does not alter this intendedmeaning of “a” or “an”.

Filter Assembly 100

FIG. 1 a shows an exemplary representation of an in vivo debris filterassembly 100 of the present invention, in a cross section of a bloodvessel 141. A filter 122 is shown in a contracted, pre-dilated, positionwith loose cords 110 attached to two struts 128 that are connected tofilter 122. Cords 110 exit filter 122 and pass through a lumen 138 andinto and through a catheter 132. Cords 110 typically exit lumen 138 exvivo, thereby allowing ex vivo manipulation by an operator.

A balloon 130 projects downstream of catheter 132 and is positionedadjacent a stenotic lesion 144. Balloon 130 typically comprises abiologically compatible elastomeric material, or semi compliancematerial, for example: rubber, silicon rubber, latex rubber,polyethylene, polyethylene terephthalate, Mylar, and/or polyvinylchloride.

In FIG. 1 b, balloon 130 has been inflated by introducing fluid througha fluid channel 148 that is substantially coaxial to catheter 130.During inflation of balloon 130, after the diameter of balloon 130reaches the distance between struts 128, continued inflation of balloon130 causes struts 128 to bias radially outwardly, thereby expandingfilter 122.

Once inflated, filter 122 filters debris 160 that is released fromstenotic lesion 144 and continues to filter debris 160 even as balloon130 is deflated, as explained below.

While filter 122 is shown in an expanded position as a generally curvedstructure, balloon 130 may alternatively have a variety of shapes,including a conus having an apex located downstream of balloon 130.

Filter 122 typically comprises a mesh sheet material that is configuredto filter debris 160 from a lumen 142. Filter 122 typically includesapertures having diameters of between at least about 20 microns and nomore than about 200 microns in diameter.

Additionally, filter 122 and/or struts 128, are configured to flexoutward until such flexion is limited by a luminal aspect 140, forexample a diameter of between 3.0 and 6.0 millimeters, depending on thesize of lumen 142 in which filter 122 is deployed.

In further embodiments, portions of filter 122 and/or struts 128comprise super elastic material, for example nitinol; an elasticmaterial; and/or a plastic material; the many materials and theirproperties being well-known to those familiar with the art.

Similarly balloon 130 has an inflation diameter of between 3.0 and 6.0millimeters, depending on the cross sectional diameter of lumen 142. Inlarger vessels 141, balloon 130 and filter 122 optionally aremanufactured to have larger maximal diameters. In smaller vessels, forexample to cut down on the bulk of deflated balloon 130 and filter 122,smaller maximal diameters are optionally appropriate.

Filter 122 comprises materials and/or apertures that aid in removablyconnecting filter 122 to an in vivo luminal aspect 140. In this manner,filter 122 remains connected to luminal aspect 140 for a period of timeafter balloon 130 has deflated, herein contracted, by egress of fluidthrough channel 148. By remaining in contact with luminal aspect 140,filter 122 continues to filter debris 160 that may be released intolumen 142 from lesion 144 while balloon 130 is in a contracted state.

In some embodiments, the material and configuration of filter 122ensures that filter 122 remains removably connected to luminal aspect140 following deflation of balloon 130. In other embodiments, filter 122includes a pressure sensitive adhesive having an affinity for luminalaspect 140 so that the adhesive, optionally in conjunction with thematerial of filter 130, remain removably connect to vessel luminalaspect 140 following deflation of balloon 130.

There are many adhesives that may be contemplated for use in providing aremovable connection of filter 122 to luminal aspect 140 including,inter alia: fibrin, biological glue, collagen, hydrogel, hydrocolloid,collagen alginate, and methylcellulose, to name a few.

Whether filter 122 comprises a mesh material alone or in combinationwith an adhesive, filter 122 is optionally configured to removablyconnect to luminal aspect 140 from a pressure exerted by balloon 130 of,for example, between one and twenty atmospheres.

In further exemplary embodiments, for example when there is continueddanger of debris 160 being generated after lesion 144 has beencompressed, balloon 130 is optionally deflated and removed from lumen142 while filter 122 is left in place. Filter 122 optionally is leftconnected to luminal aspect 140 by the configuration of filter 122and/or biological glues noted above until the danger of generation ofdebris 160 has passed.

As noted above, during a typical balloon angioplasty, balloon 130 issequentially inflated to a pressure of several atmospheres and deflated.In exemplary embodiments, filter 122 remains removably connected toluminal aspect 140 following the first inflation of balloon 130 andthroughout several sequences of inflation and deflation.

As filter 122 is deployed relatively proximate to lesion 144 whereluminal aspect 140 generally comprises unhealthy tissue, the chance thatfilter 122 will cause damage to healthy tissue of luminal aspect 140 isvery low.

Additionally, the proximity of filter 122 to balloon 130 substantiallylowers the odds that a branch artery will be located between filter 122and balloon 130, to act as a conduit for debris 160. Further, as balloon130 and filter 122 are deployed on single catheter 132, the cost foreach assembly 100 should be lower than existing technology employing aseparate filter. Moreover, as assembly 100 includes balloon 130 andfilter 122 mounted on a single catheter, the complexity of manufacture,deployment and the surgical fees to the surgeon should be reduced overexisting technology.

As seen in FIG. 1 c, after stenotic lesion 144 has been cracked andsquashed radially outwards, balloon 130 is deflated and filter 122remains in an expanded state and continues to capture debris 160. As thefluid contained in lumen 142 is moving in a direction 162, in a distalor downstream direction with respect to filter 122, debris 160 remainsin place, captured within filter 122.

As used herein, the terms distal and distally refer to a position and amovement, respectively, in downstream direction 162.

To disconnect filter 122 from luminal aspect 140, cords 110 are pulledproximally, upstream, in a direction 164. As used herein, the termsproximal and proximally refer to a position and a movement,respectively, in upstream direction 164.

While cords 110, as shown, pass through catheter lumen 138, inalternative embodiments, cords 110 pass to the side of balloon 130without passing through a lumen 138. Further, while balloon 130 is shownattached to catheter, 132, there are many alternative options fordelivering balloon 130 and filter 122, for example using a guide wire.Those familiar with the art will readily recognize the many alternativemodes and configurations available for delivery and operation of balloon130 and filter 122.

In an exemplary embodiment, filter 122 is configured to disconnect fromluminal aspect 140 in response to tension applied to cords 110 of atleast about one Newton and no more than about 20 Newtons.

As the diameter of lumen 142 is larger than the diameter of catheterlumen 138, continued upstream pull in direction 164 on cords 110, biasesthe proximal portions of struts 128 radially inward, causing theproximal edges of filter 122 to move radially inward so that filter 122disconnects from luminal aspect 140. Following disconnection of filter122 from luminal aspect 140, continued pulling of cords 110 in direction164 causes struts 128 to inwardly bias, thereby reducing the upstreamcross sectional diameter of filter 122.

As the fluid in lumen 142 travels distally in direction 162, pullingcatheter 132 and filter 122 in proximal direction 164 causes debris 160to move downstream against filter 122 so that debris 160 remainscaptured by filter 122.

Thus, filter 122 maintains captured debris 160 even when there is adistance between struts 128, as might occur when there is considerablevolume of debris 160, for example in large arteries. Optionally, cords110 are pulled in direction 164 until a portion of filter 122 contactsballoon 130 and/or enters catheter lumen 138.

While two struts 128 are shown connected to two cords 110, the presentembodiments, contemplate four or even eight struts 128, with each strut128, or each pair of struts 128, being attached to individual cords 110that remove filter 122 from luminal aspect 140.

Alternatively, assembly 100 contemplates using a single strut 128 with asingle cord 110 connected to single strut 128 that encircles filter 122and slidingly attaches to strut 128 in a lasso configuration. Pulling onsingle cord 110 causes contraction of struts 128 and of the associatedcross-sectional circumference of filter 122, thereby preventing egressof debris 160 filter 122. The many options available for configuringcords 110 and struts 128 to effectively close filter 122 are well knownto those familiar with the art.

Filter Assembly 200

FIG. 2 a shows an exemplary embodiment of an assembly 200 in which asingle cord 112 passes distally in direction 162 through catheter lumen138. Cord 112 then curves within filter 122 to pass in a proximaldirection 164 into a cord inlet 184 and through a cord channel 120. Cordchannel 120 guides cord 112 circumferentially around filter 122. Aftercircling filter 122, cord 112 exits channel 120 through cord outlet 186and passes distally in direction 162 into filter 122. Cord 112 thencurves within filter 122 to pass in a proximal direction 164 into andthrough catheter lumen 138.

In this manner both ends of cord 112 exit catheter lumen 138 and, bypulling both ex vivo ends of cord 112 in direction 164, filter 122 iscontracted along channel 120, as seen in FIG. 2 d. While a single cord112 is shown, channel 120 optionally comprises multiple pairs of inlets184 and outlets 186, each associated with a separate cord 112. The manyconfigurations and modifications of channel 120, inlet 184, and outlet186 are well known to those familiar with the art.

FIG. 2 d shows an exemplary embodiment of a tubular compression sleeve134 that is coaxial with catheter 132. Sleeve 134 has been slidinglypushed through vessel lumen 142 in direction 162 until sleeve 134approaches filter 122.

In an exemplary embodiment, pulling cord 112 and/or catheter 132 indirection 164 while holding sleeve 134 substantially stationary pullsfilter 122 into compression sleeve 134. Alternatively, compressionsleeve 134 is advanced in direction 162 while catheter 132 and/or cord110 are held substantially stationary.

In an exemplary embodiment, compression sleeve 134 serves as a housingfor filter 122 to prevent filter 122 from scraping along luminal aspect140 during removal from lumen 142. Additionally or alternatively,compression sleeve 134 serves to compress filter 122 into a smallermaximal circumferential diameter so that filter 122 more easily passesthrough lumen 142 during removal of filter 122.

Balloon Assembly 300

In embodiments, balloon 130 optionally includes alternative shapes, forexample having varied cross sectional diameters. As seen in assembly 300(FIG. 3 a), the diameter associated with a distal portion 133 ofdeflated balloon 130 is larger than the diameter associated with aproximal portion 139.

As seen in FIG. 3 b, filter 122 reaches a maximal diameter initially asdistal balloon portion 133 inflates. In this manner, filter 122 is fullyin position and expanded prior to inflation of proximal balloon portion139.

As seen in FIG. 3 c, proximal balloon portion 139 has been fullyinflated to compress lesion 144, thereby releasing debris 160 that iscaptured by filter 122. The many options for configuring alternativeshapes of balloon 130 are well known to those familiar with the art.

Balloon and Filter Assembly 400

There are additionally many methods of assembling filter 122 and balloon130, as seen in assembly 400 (FIG. 4). In a non-limiting embodiment,balloon 130 is seen having an overall length 209 of approximately 38millimeters and a maximal inflation diameter 211 of approximately 5millimeters.

Additionally, balloon 130 is shown with a proximal portion 207 having alength 235 of approximately 18 millimeters and a distal portion 208having a length 233 of approximately 18 millimeters.

In an exemplary embodiment, filter 122 extends to substantially coverdistal portion 208 while proximal portion 207 is unprotected by filter122.

In alternative configurations of assembly 400, filter 122 optionallysubstantially fully covers distal balloon portion 208 and extends overat least a portion of proximal balloon portion 207; the manyconfigurations of assembly 400 being well known to those familiar withthe art.

Dual Balloon Assembly 500

Assembly 500 (FIGS. 5 a-5 e) demonstrates just one more of the manyembodiments of the instant invention that are easily contemplated bythose familiar with the art. Assembly 500 comprises a proximal balloon230 and a distal balloon 101. As seen in FIG. 5 b, distal balloon 101 isinflated to expand filter 122 and substantially take up the volumewithin filter 122. As seen in FIG. 5 c, proximal balloon 230 is inflatedseparately and pressed against lesion 144.

After deflation of proximal balloon 230 as seen in FIG. 5 d, distalballoon 101 remains inflated so that debris 160 remains proximal todistal balloon 101. Upon deflation of distal balloon 101, debris 160enters and is captured by filter 122.

Alternative Environments

While assemblies 100-500 have been described with respect to vessel 141,assemblies 100-500 can be easily configured for use in a wide variety ofin vivo lumens 142 including inter alia: a lumen of a urethra, a biliarylumen and/or a renal calyx lumen. Additionally or alternatively, filter122 can be easily modified to capture debris in virtually any in vivolumen 142 including, inter alia: biliary stones and/or renal stones. Themany applications, modifications and configurations of assemblies100-500 for use in virtually any in vivo lumen 142 will be readilyapparent to those familiar with the art.

Materials and Design

In embodiments, filter 122 comprises a sheet material configured toextend distally with respect to balloon 130 while filter 122 isexpanded. In embodiments, the sheet material of filter 122 is selectedfrom the group consisting of: meshes and nets.

In embodiments, bending of a portion of the sheet material of filter 122forms filter cord channel 120. In embodiments, attaching a shapedcomponent to filter 122 forms filter cord channel 120.

In embodiments, the material of filter 122 has a thickness of at leastabout 20 microns. In embodiments, the material of filter 122 has athickness of no more than about 200 microns. In embodiments, thematerial of filter 122 includes apertures having diameters of at leastabout 20 microns. In embodiments, the material of filter 122 includesapertures having diameters of no more than about 80 microns in diameter.In embodiments, the material of filter 122 is manufactured using atechnique from the group of techniques consisting of: interlacing,knitting, weaving, braiding, knotting, wrapping, and electro spinning.

In embodiments, filter 122 is configured to expand to a cross sectionaldiameter of at least about 1.0 millimeters. In embodiments, filter 122is configured to expand to a cross sectional diameter of no more thanabout 6.0 millimeters. In embodiments, the extent of the expansion offilter 122 is configured to be limited by the walls of luminal aspect140 in which filter 122 is deployed.

In embodiments, balloon 130 has a maximum inflation diameter of at leastabout 1.0 millimeter. In embodiments, balloon 130 has a maximuminflation diameter of no more than about 6.0 millimeters.

In embodiments, balloon 130 has a wall thickness of at least about 0.2millimeters. In embodiments, balloon 130 has a wall thickness of no morethan about 0.5 millimeters.

In embodiments, strut 128 has a substantially circular cross sectionhaving a diameter of at least about 0.1 millimeters. In embodiments,strut 128 has a substantially circular cross section having a diameterof no more than about 0.6 millimeters.

In embodiments, strut 128 has a cross section having greater and lessermeasurements and the greater measurement is at least about 0.1millimeters. In embodiments, strut 128 has a cross section havinggreater and lesser measurements and the greater measurement is no morethan about 0.6 millimeters. In embodiments, strut 128 has a crosssection having greater and lesser measurements and the lessermeasurement is at least about 0.1 millimeters. In embodiments, strut 128has a cross section having greater and lesser measurements and thelesser measurement is no more than about 0.6 millimeters.

In embodiments, filter 122 has an internal and an external aspect andstrut 128 is attached to the internal aspect or the external aspect offilter 122. In embodiments, strut 128 is attached to filter 122 using aprocess selected from the group consisting of: sewing, adhesion, gluing,suturing, riveting and welding.

In embodiments, cord channel 120 comprises at least two cord channels;and cord 112 comprises at least two cords.

In embodiments, catheter 132 has an outside diameter of at least about1.0 millimeter. In embodiments, catheter 132 has an outside diameter ofno more than about 5.0 millimeters. In embodiments, catheter 132 has alength of at least about 0.8 meter. In embodiments, catheter 132 has alength of no more than about 1.5 meters.

In embodiments, the walls of catheter 132 compression sleeve 134 have athickness of at least about 2 millimeters. In embodiments, the walls ofcatheter 132 compression sleeve 134 have a thickness of more than about5 millimeters.

In embodiments, filter 122, cord 110 (FIG. 1 a) and cord 112 (FIG. 2 a),strut 128, compression sleeve 134, and catheter 132, comprise a materialfrom the group consisting of: polyethylene, polyvinyl chloride,polyurethane and nylon.

In embodiments, filter 122, cord 110 (FIG. 1 a) and cord 112 (FIG. 2 a),strut 128, compression sleeve 134, and catheter 132, comprise a materialselected from the group consisting of: nitinol, stainless steel shapememory materials, metals, synthetic biostable polymer, a naturalpolymer, and an inorganic material. In embodiments, the biostablepolymer comprises a material from the group consisting of: a polyolefin,a polyurethane, a fluorinated polyolefin, a chlorinated polyolefin, apolyamide, an acrylate polymer, an acrylamide polymer, a vinyl polymer,a polyacetal, a polycarbonate, a polyether, an aromatic polyester, apolyether (ether keto), a polysulfone, a silicone rubber, a thermoset,and a polyester (ester imide).

In embodiments the natural polymer comprises a material from the groupconsisting of: a polyolefin, a polyurethane, a Mylar, a silicone, apolyester and a fluorinated polyolefin.

In embodiments, filter 122, cord 110 (FIG. 1 a) and cord 112 (FIG. 2 a),strut 128, compression sleeve 134, and catheter 132, comprise a materialhaving a property selected from the group consisting of: compliant,flexible, plastic, and rigid.

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention, which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable subcombination.

Although the invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives, modificationsand variations will be apparent to those skilled in the art.

Accordingly, the invention is intended to embrace all such alternatives,modifications and variations that fall within the spirit and broad scopeof the appended claims. All publications, patents and patentapplications mentioned in this specification are herein incorporated intheir entirety by reference into the specification, to the same extentas if each individual publication, patent or patent application wasspecifically and individually indicated to be incorporated herein byreference. In addition, citation or identification of any reference inthis application shall not be construed as an admission that suchreference is available as prior art to the present invention.

1. An assembly for filtering debris flowing in an in vivo fluid stream,the assembly comprising: i) at least one balloon configured tovolumetrically expand and, during at least a portion of said expansion,operatively connect with a filter, and to contract following saidexpansion; ii) a filter configured to operatively connect with said atleast one balloon during at least a portion of said volumetric expansionof said at least one balloon, such that said filter expands during saidoperative connection in order to filter debris from a fluid flowing in afluid stream within which said expanded filter is disposed, wherein saidfilter includes: a) a distal portion; b) a proximal portion; c) anopening to said filter associated with said proximal portion; and d) atleast one cord guide channel circumferentially encircling at least aportion said proximal portion. 2-10. (canceled)
 11. The assemblyaccording to claim 1, wherein at least a portion of said filter isconfigured to removably connect to a luminal aspect associated with saidfluid stream, in response to pressure of between at least about oneatmosphere and no more than about 20 atmospheres.
 12. The assemblyaccording to claim 1, wherein at least a portion of said filter isconfigured to remain removably connected to a luminal aspect during saidcontraction of said at least one balloon. 13-14. (canceled)
 15. Theassembly according to claim 12, including at least one cord passingthrough said at least one cord guide channel and operatively associatedwith said filter and configured to disconnect at least a portion of saidfilter from said luminal aspect when tension is applied to said at leastone cord.
 16. The assembly according to claim 15, wherein said at leasta portion of said filter is configured to disconnect from said luminalaspect in response to tension applied to said at least one cord of atleast about one Newton.
 17. The assembly according to claim 15, whereinsaid at least a portion of said filter is configured to disconnect fromsaid luminal aspect in response to tension applied to said at least onecord of no more than about 20 Newtons.
 18. The assembly according toclaim 1, wherein at least a portion of said filter includes apressure-sensitive adhesive having an affinity for a tissue associatedwith an in vivo luminal aspect. 19-26. (canceled)
 27. The assemblyaccording to claim 12, including a compression sleeve comprising asubstantially curved wall having a proximal end, a distal end and alumen extending from said proximal end to said distal end, said lumenhaving a cross sectional diameter that is substantially smaller than themaximal cross sectional diameter of said luminal aspect
 28. The assemblyaccording to claim 27, including at least one cord passing through saidat least one cord guide channel and operatively associated with saidfilter, at least a portion of said at least one cord movingly juxtaposedwithin said compression sleeve lumen.
 29. The assembly according toclaim 28 wherein when said at least one cord operatively associated withsaid filter is held relatively stationary during a first distal movingof said compression sleeve, said filter is caused to disconnect fromsaid luminal aspect.
 30. The assembly according to claim 28, wherein inresponse to at least one second distal moving of said sleeve while saidat least one cord is held relatively stationary, said filter is causedto radially contract such that a maximal cross sectional diameter ofsaid filter is smaller than a cross sectional diameter of said sleevelumen.
 31. The assembly according to claim 30, wherein in response to atleast one third distal moving of said sleeve while said at least onecord is held stationary, at least a portion of said filter is caused toenter said sleeve lumen.
 32. The assembly according to claim 15,wherein: i) said at least one balloon comprises an outer wall having adistal end and a proximal end and an inner wall defining a lumen, saidlumen extending from said distal end to said proximal end; and ii) atleast a portion of said at least one cord is configured to slidinglypass through said lumen.
 33. (canceled)
 34. The assembly according toclaim 32, including a catheter having a distal end and a proximal endand a lumen extending from said distal end to said proximal end, whereinsaid at least one balloon proximal end is operatively associated withsaid distal end of said catheter.
 35. The assembly according to claim34, wherein said at least one balloon lumen is substantially continuouswith said catheter lumen.
 36. The assembly according to claim 34,wherein at least a portion of said at least one cord additionallyextends through said catheter lumen. 37-48. (canceled)
 49. The assemblyaccording to claim 1, wherein said filter comprises a flexible sheetmaterial and said guide channel is formed from at least one of: abending of a portion of said sheet material; and a shaped componentattached to said sheet material.
 50. The assembly according to claim 1,including at least one cord, at least a portion of said at least onecord passes through said guide channel, such that at least a portion ofsaid opening is configured to contract radially inwardly in response totension applied to said at least one cord.
 51. The assembly according toclaim 50, wherein said at least one cord channel comprises at least twocord channels and said at least one cord comprises at least two cords,said at least two cord channels being located substantially on the samecross sectional plane of said filter.
 52. An assembly for filteringdebris flowing in an in vivo fluid stream, the assembly comprising: i)at least one balloon configured to volumetrically expand and to contractfollowing said expansion; and ii) a filter comprising a material havingtissue connective properties for a portion of luminal tissue associatedwith an in vivo fluid stream, said filter positioned to operativelyconnect with said at least one balloon during at least a portion of saidexpansion and removably connect to least a portion of said tissue andremain so connected during said contraction of said at least oneballoon, wherein said filter includes: a) a distal portion; b) aproximal portion; c) an opening to said filter associated with saidproximal portion; and d) at least one cord guide channelcircumferentially encircling at least a portion said proximal portion.53-83. (canceled)